Quote Originally Posted by utevanwgn View Post
I don't know about cars drawing air from outside when in defog.
In my experience in very humid conditions some manufacturers recommend using the ac circuit to dehumidify the air and if needed the heater to worm it up again. Have a read of the owners user manual.
The inderdash units all have drains for condensation that it is going to make water is a given.
Blowing hot wet air at a cold windscreen is instant fog material. Ive allways had better results demisting screens with the ac on. Try it sometime or don't you have aircon.
Air pressure between the sealed cavity behind the B pillar (if it is sealed ) and the inside of the cab is not going to be effected by outside air pressure .
There is also no such thing as never.
Yeah I fitted the integrated air into my WB. I have also had to keep the AC working in 35 year old tractors on my farm for the last 10 years, plus all the other gear on my farm.
Once again someone has not read the thread and then replied half cocked. I actually wrote; most cars draw the air from outside when on defogger. Not on recirculate.
Yes it is a given that you run the heater and AC to defogger your windscreen. But never on recirculate. If yu put the evaporated in that cavity, it effectively has no option but recirculate. Your car will fog up fantastically even with heat and AC on.
The other point you didn't read was the receiver drier, not the evaporator. It will build up condensation and rust the floor out. It needs to be in the engine bay. Not to mention you have to pull the dash out when ever you re-gas because you need to change the receiver drier. Just trying to point out that it is just dripping straigt onto the floor pan. I realise the evaporator has a drain.